This invention relates to a dead bolt for a cylinder lock and particularly to an adjustable dead bolt assembly which has an adjustable bolt extension member to be connected to a cylinder lock.
Typically the bolt, which can be put into a locking position and an unlocking position by the actuation of a cylinder lock, is housed in a bolt casing capable of being mounted in a door and is incorporated with a crank plate capable of being connected to the cylinder lock. Generally, the bolts presently available are of two sizes, one being 23/8 inches or 60 mm and the other being 23/4 inches or 70 mm, and their lengths are not adjustable. In buying a bolt, the user must get a bolt of a length which suits the specification of the door. Sometimes, inconvenience may cause to the user if he buys a bolt of the wrong specification. Therefore, an improvement is desirable to obtain a bolt of adjustable length.